I think its a combination of two things..
on my 3 axis machines I have a Xylotex board,
one is 3 motor setup .. the other is a 4 motor set up using,
TurboCNC and Mach2 .. those programs donít seem to care if the control board is powered on they just run..
I noticed on my foam cutter GMFC will not run unless the control board is powered on the board is a HobbyCNC unit.
so I think the GMFC is looking for a signal that its powered on, maybe even that each step is taking place... ( but donít ďĒ me on that.. )
Mostly I just followed instructions on how to wire up each board.. and it all worked :-)
What is the 3 axis configuration look like for foam is it the same Ö
Did you just replace the router ..with a heating element ?
In GMFC the pin direction and Step pins are all under Windows Device Manager, But for me I did not have to change anything the defaults here good..
Not sure if any of this helps you..